3-D reconstruction by extended depth-of-field in failure analysis – Case study I: Qualitative fractographic investigation of fractured bolts in a partial valve

Extended depth-of-field 3-D reconstruction is an image processing based technique associated to optical microscopy for qualitative or quantitative analysis of surfaces topographies. It is proposed here as a low-cost alternative to scanning electron microscopy or confocal laser scanning microscopy methods in some cases in failure analysis. A case study of fractured bolts in a partial valve from a petrochemical plant is presented in this paper to illustrate a qualitative fractographic investigation using this technique.